I’m a photographer and it’s important to me that my MacBook Pro screen/display remain calibrated. So to that end, I’ve removed the Brightness controls from the TouchBar so that I don’t accidentally change it. I ran my X-rite ColorMunki calibration tool yesterday, and adjusted the brightness (but not the color or contrast) to 120 cd/m2. In Display, I have both “Automatically Adjust Brightness” and “True Tone” disabled, and in the software I have “Adjust brightness, contrast, and RGB gains manually” enabled. So today I went to a cafe to cull my photos, and the display was much darker than it should be. Just getting home, I reran the calibration software, and the brightness was 59 cd/m2! What gives? Any ideas on why the display’s brightness would have changed without my intervention?
I have solutions but I need to know which macBook Pro you have. Intel or Apple silicon?
I have a 2019 16" MacBook Pro (Intel)
It was easier some years ago, and that was what I remembered when I answered you, sorry.
Looking at my notes, I have discovered that the solution to this problem on Intel now involves installing an application via terminal and then using an Automator script to correct the brightness every time it changes.
If you are comfortable downloading source code and using make to install an app, I can write up a description and share the Automator script. You will need to install Xcode Command Line Tools and maybe also Xcode application.
I do not know why this happens, but I have had this problem off and on for 7 years (or more) on Intel MacBook Pro. It is very irritating since, as a professional image editor and photographer, I rely on my display to be calibrated. This made me desperate enough to make a workaround. I now use an Apple silicon MacBook Pro and this is not a problem anymore. But I still use my 2015 MacBook Pro and there I still use the Automator script.
Exactly. I’m in a cafe processing client’s images, and the screen needs to be accurate, which is why I calibrate it. I think the issue may be caused by “Automatic graphics Switching” which I had enabled in the Battery panel.